John c



UNITED STATES PATENT OFFICE.

JOHN C. SELLARS, OF BIRKENHl JAD, COUNTY OF CHESTER, ENGLAND.

COMPOSITION FOR MOLDS AND COMPOSITION-MOLD FOR FORMING CONCRETE.

SPECIFICATION forming part of Letters Patent No. 244,321, dated -J'uly 12, 1881.

Application filed May 31, 1881. (No specimens.) Patented in England April 9, 1877.

, date April 9, 1877,) of which the following is a specification.

Concrete, artificial stone, cement, and like substances have not hitherto been made available for ornamental purposes generally, or where great diversity of form or shape has been requisite, on account of the difficulty of giving the desired outline to the said concrete, artificial stone, cement, and like substances.

Now the object of my invention is to provide a com position of matter specially adapted for the formation of molds in which to pour or fill concrete, artificial stone, cement, or like substances, in a liquid or semi-liquid condition, so as to obtain a casting of sharp, clear, and welldefined outline, and of smooth, neat, and finished appearance.

The great obstacle to making castings of concrete or artificial stone has been the facility with which such concrete or stone has adhered to the surface of the mold, rendering the removal of the casting from the said mold difficult, and a disfigured and rough article, quite unfit for use from an artistic point of view, has been produced.

By my invention perfect concrete or like castings of any form or design obtainable in metal can be easily formed, and the invention is specially applicable to the manufacture of letters and objects decorated with foliage and other complicated designs.

In carrying my invention into practice the molds in which the concrete, artificial stone, cement, or like substances are cast are formed or made of the following ingredients combined in the proportions stated: sand, charcoal, or finely-divided material,one hundred parts,by weight; paraffine or similar wax-like substance unacted upon by alkaline matter, from six to eleven parts, by weight.

Molds made with ninety-three parts, by weight, of sand and seven, by weight, of paraffine answer well.

The impressions are formed in the composition by means of patterns, as is usual in makiug molds for metal casting.

To insure that the casting shall be smooth and well finished, steam or hot air is passed over the surface of the composition-mold before the concrete or thelike is poured orfilled in.

What I claim, and desire to secure by Letters I mo. 0. SELLARS.

Witnesses J. JOHNSON, J. RIGHMAN. 

